It sells for $90 for a 40 mL bottle, which might seem like a lot of money until you consider how strong it is. It has 26.3 mg of THC per millilitre, so the bottle contains 1,052 mg of THC.

(Recreational products will be similar in strength, format and pricing, said Canopy Growth vice-president Jordan Sinclair.)

If you were a daily user with a 5 mg dose – on the small to moderate side – that would last you for most of a year (and cost a thrifty 43 cents per dose.) If you microdosed at 2.5mg, it would last a lot longer than that.

And all that will probably be fine if you’re paying close attention and following the instructions. But there’s not much in the way of a safety net if you miscalculate, and it’s not hard to miscalculate.

“Oils are kind of the softer, entry-level to using cannabis, but it’s so much trickier,” says University of British Columbia post-doctoral student Jenna Valleriani. “There needs to be more information. Rather than just using dried cannabis, where you can take one inhalation, see how you feel and stop, and kind of figure out if you need more or not, with oils without that proper education, it’s so easy to consume too much.”

“Instinctively, you might take a whole dropper and put it in your mouth. It’s not even that much liquid. There’s obviously an enormous potential for folks to overconsume and have an unenjoyable experience.”

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Users do have to pay close attention, Sinclair says.

“If you think about the risk of overconsumption, smoking versus oils, it is much easier to have too much when you’re talking about ingesting oils.”

“Almost everybody that you run into has some alcohol that they had too much of when they were 17 years old, and they’ll never drink it again. We don’t want that scenario for cannabis.”

Canopy’s oils will come with clear dosing information, he says.

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Start low, go slow

Sinclair recommends a “start low, go slow” approach for beginners — take a very small dose and no more for hours, maybe a day, until you’ve had a chance to judge its effects on you.

People new to edibles often decide they’re not working and take more, warned Jason Busse of McMaster University’s Centre for Medicinal Cannabis Research.

‘It can take some time to feel the effects, and that there should be a real caution about exceeding quite low doses, for those that are trying this for the first time, because they can get themselves into real trouble.”

Fewer and fewer Canadians smoke tobacco, and it wouldn’t be surprising if only a limited number wanted marijuana in smoked form. In Colorado, only about half of the cannabis products sold are designed to be smoked, according to data from the GreenEdge Cannabis Retail Sales Tracking System.

(With factory-made edibles not on the market yet, it wouldn’t be surprising if oil had a much bigger market share than it did in the U.S.)

Cannabis gel capsules, which will also be available on Day 1, will give users a more foolproof system, Sinclair says.

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Online sales take away another guardrail

One problem with buying cannabis oil online, rather than in a store, is that there’s no longer a person whose job it is to warn you to be careful about dosing, and explain why, Valleriani says. (Ontario will have online-only cannabis sales until next April, but all provinces will have an option for online ordering.)

“For me, one of the big shames of having to wait until next April (in Ontario) to have storefronts is that now we’re losing that point of education and harm reduction with consumers. Now we have these online channels. I’m sure there’s going to be someone you can call, but now we’re missing all of that really important face-to-face contact that could have happened with the stores.”

Warnings that come with an online cannabis order are much easier to ignore than a human being, Busse says.

“There’s nothing to stop people from not looking at it carefully, going through it very quickly, and you do run the risk of people ordering products that they simply haven’t had enough education on to use in a way that’s likely to be safe.”

“For individuals who have been paying close attention, they’re likely to be fine.”

“But there is that potential where somebody who hasn’t taken the time to read the educational material carefully, haven’t had the opportunity to have a conversation with someone who has made some of those points clear to them, there is the potential for someone to take a lot more THC than they intended.”